U.S. patent application number 15/511184 was filed with the patent office on 2017-09-14 for a high exchange-capacity anion exchange resin with dual functional-groups and method of synthesis thereof.
The applicant listed for this patent is NANJING UNIVERSITY, NANJING UNIVERSITY YANCHENG ENVIRONMENTAL PROTECTION TECHNOLOGY ANDENGINEERING RESEARCH INST. Invention is credited to Chen CHEN, Cheng CHENG, Jinnan WANG, Yi WANG, Xin YANG.
Application Number | 20170259255 15/511184 |
Document ID | / |
Family ID | 51765123 |
Filed Date | 2017-09-14 |
United States Patent
Application |
20170259255 |
Kind Code |
A1 |
WANG; Jinnan ; et
al. |
September 14, 2017 |
A HIGH EXCHANGE-CAPACITY ANION EXCHANGE RESIN WITH DUAL
FUNCTIONAL-GROUPS AND METHOD OF SYNTHESIS THEREOF
Abstract
The present disclosed are a high exchange-capacity anion
exchange resin with dual functional-groups and method of synthesis
thereof. The invention relates to the field of environmental
function material synthesis and application. The resin is based on
chloromethylated polystyrene-divinylbenzene polymer as matrix, and
by primary amination and quaternization, yields an anion exchange
resin with dual functional-groups having both a weak base anionic
group and a strong base anionic group. The anion exchange resin not
only has high adsorption capacity for water-born nitrate ions, but
also can effectively squelch natural organic acids such as phytic
acid in water, thus simultaneously removing nitrate ions and phytic
acid organic matter from water. Therefore, the resin has a broad
application potential in the fields of drinking water treatment,
groundwater remediation, and advanced urban sewage treatment.
Inventors: |
WANG; Jinnan; (Nanjing,
Jiangsu, CN) ; WANG; Yi; (Nanjing, Jiangsu, CN)
; YANG; Xin; (Nanjing, Jiangsu, CN) ; CHENG;
Cheng; (Nanjing, Jiangsu, CN) ; CHEN; Chen;
(Nanjing, Jiangsu, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
NANJING UNIVERSITY
NANJING UNIVERSITY YANCHENG ENVIRONMENTAL PROTECTION TECHNOLOGY
ANDENGINEERING RESEARCH INST |
Nanjing, Jiangsu
Yancheng, Jiangsu |
|
CN
CN |
|
|
Family ID: |
51765123 |
Appl. No.: |
15/511184 |
Filed: |
July 13, 2015 |
PCT Filed: |
July 13, 2015 |
PCT NO: |
PCT/CN2015/083880 |
371 Date: |
March 14, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08F 8/44 20130101; C08F
8/32 20130101; B01J 41/13 20170101; C08F 8/32 20130101; C08F 8/32
20130101; C08F 12/28 20130101; B01J 41/07 20170101; C08F 8/12
20130101; C08F 8/32 20130101; C08F 12/18 20130101; C08F 12/18
20130101; C08F 8/12 20130101; C08F 8/32 20130101; C08F 8/02
20130101; B01J 41/05 20170101; C08F 12/24 20130101; C08F 8/32
20130101; C08F 12/18 20130101; C08F 212/36 20130101; C08F 8/12
20130101; C08F 12/18 20130101 |
International
Class: |
B01J 41/13 20060101
B01J041/13; C08F 212/36 20060101 C08F212/36; C08F 8/44 20060101
C08F008/44 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 15, 2014 |
CN |
201410335922.8 |
Claims
1. A high exchange-capacity anion exchange resin with dual
functional-groups, wherein chloromethylated
polystyrene-divinylbenzene polymer serves as matrix, onto which
primary amine is grafted to form a weak base anion exchange group,
3-chloro-2-hydroxypropyltrimethylammonium chloride is subsequently
grafted onto the primary amine to form a strong base anion exchange
group, generating the high exchange-capacity anion exchange resin
with the weak base and the strong base dual functional-groups,
wherein the resin having the general formula I: ##STR00006##
wherein m is the degree of polymerization and within the range of
3000 to 5000.
2. The high exchange-capacity anion exchange resin with dual
functional-groups according to claim 1, wherein the total exchange
capacity of the anion exchange resin is 6.3.about.7.9 mmol/g,
wherein the strong base exchange capacity is 3.8.about.4.7 mmol/g,
the weak base exchange capacity is 2.5.about.3.2 mmol/g, and the
average particle diameter of the resin is 550.about.650 .mu.m.
3. A method for synthesizing a high exchange-capacity anion
exchange resin with dual functional-groups, comprising the steps
of: (1) a primary amination reaction, wherein, into a mixed
solution of absolute ethanol and chloroform, chloromethylated
polystyrene-divinylbenzene polymer was dissolved to swell,
hexamethylenetetramine was added, the reaction mixture was stirred
at 35-45.degree. C. for 6-7 hours; the polymer was filtered, washed
with ethanol, and placed into a mixed acid solution of concentrated
hydrochloric acid-absolute ethanol, with the chloromethylated
polystyrene-divinylbenzene polymer (g):mixed acid solution
(ml)=1:4-5, the reaction was kept at 35-45.degree. C. for 2-3
hours, the polymerized product was filtered again, washed with
water, allowed to transition for 2-3 hours with NaOH solution added
to keep pH>14, washed with water, and filtered to afford
poly(divinylbenzene-vinylbenzyl amine) polymers; and (2) a
quaternization reaction, wherein, to a mixed solution formulation
of 3-chloro-2-hydroxypropyltrimethylammonium chloride aqueous
solution and NaOH, the poly(divinylbenzene-vinylbenzyl amine)
polymers from step (1) is added, with the
poly(divinylbenzene-vinylbenzyl amine) polymers (g):the mixed
solution formulation (ml)=1-2:50, the reaction mixture was stirred
at 70-80.degree. C. for 2-3 hours, the product was washed with
10-30% HCl solution and deionized water, dried in vacuum at
40-60.degree. C., to afford high exchange-capacity anion exchange
resin with dual functional-groups.
4. The method for synthesizing the high exchange-capacity anion
exchange resin with dual functional-groups according to claim 3,
wherein, in the step (1), into a mixed solution of absolute ethanol
and chloroform, chloromethylated polystyrene-divinylbenzene polymer
was dissolved to swell at 20-25.degree. C. for for 3-4 hours; with
the ratio of chloromethylated polystyrene-divinylbenzene polymer
(g):absolute ethanol (ml):chloroform (ml):hexamethylenetetramine
(g) being equal to 5:15.about.20:2.about.4:4.about.5.
5. The method for synthesizing the high exchange-capacity anion
exchange resin with dual functional-groups according to claim 3,
wherein, the mixed acid solution of concentrated hydrochloric
acid-absolute ethanol in the step (1) is a mixed acid solution
formulation of 37.5% (mass %) concentrated HCl mixed with absolute
ethanol, with concentrated HCl (m1):absolute ethanol (ml) in the
range of 1:2-3.
6. The method for synthesizing the high exchange-capacity anion
exchange resin with dual functional-groups according to claim 3,
wherein NaOH solution was added to keep pH>14 to transition for
2-3 hours, wherein the NaOH solution is 1% (mass %).
7. The method for synthesizing the high exchange-capacity anion
exchange resin with dual functional-groups according to claim 3,
wherein the 3-chloro-2-hydroxypropyltrimethylammonium chloride
aqueous solution in the step (2) is 60% (mass %), the NaOH solution
is 40% (mass %), and the ratio between the
3-chloro-2-hydroxypropyltrimethylammonium chloride aqueous solution
and the NaOH solution is 8-10:1 in volume.
8. The method for synthesizing the high exchange-capacity anion
exchange resin with dual functional-groups according to claim 3,
wherein the vacuum drying step is performed under the pressure of
-0.09.about.-0.08 MPa for 12-24 hours.
Description
FIELD
[0001] The invention discloses an anion exchange resin and method
of synthesis thereof, more specifically, a high exchange-capacity
anion exchange resin with dual functional-groups and method of
synthesis thereof, wherein chloromethylated
polystyrene-divinylbenzene polymer serves as matrix, and by primary
amination and quaternization, yields the high exchange-capacity
anion exchange resin with dual functional-groups, and method of
synthesis thereof.
BACKGROUND
[0002] In recent years, water resources, especially groundwater
resources have experienced serious pollution, resulting in various
direct or latent harm and threats to ecological systems and humans.
Among these harm and threats, the heavy use of nitrogen fertilizer
in agriculture and the discharge of nitrogen-containing have led to
increased concentration of nitrate ion that well exceeded the
threshold of waterbody self-purification. Excessive intake of
nitrate ions by humans may cause serious health problems, such as
birth defects, diarrhea, abdominal pain, diabetes, high blood
pressure. Removing nitrate ions from water is of significant
benefits. Commonly used methods for removing nitrate ions from
water includes mainly biochemical method, chemical reduction
method, electro-osmosis method, and adsorption method. The
biochemical method has a relatively long processing cycle, and its
outcome is heavily seasonally dependent. The chemical reduction
method requires finicky conditions, making it difficult for
large-scale application. The electro-osmosis method comes with a
high processing cost that render it unfit for long-term use. The
ion exchange and absorption method is considered the ideal solution
because of the advantages of being simple, fast and efficient, low
cost, and renewable. Guoming Cao and others have achieved
relatively good result using a strong base anion exchange resin in
treatment of nitrate contamination of groundwater, (Guoming cao,
Mei Sheng, YuLei Fei, Kerwei, Weiwei Shi, and Yifeng Yu, ion
exchange method by continuous flow process in treatment of nitrate
contaminated groundwater, Water Purification Technology, 2011, 30
(5): 90-94). On the other hand, organic matter in urban sewage,
wastewater, biochemical tail water, or natural waterbodies, are
mainly of plant type, which produce undesirable odor and smell,
degrade water quality, and generate disinfection byproducts harmful
to human health during water disinfection treatment process. The
prevailing effective adsorbent material for removing this type of
natural organic matter is weak base anion exchange resin.
[0003] Typically, the functional group in an anion exchange resin
is amino group or quaternary ammonium group, the adsorption
capacity for nitrate ions is controlled by the number of functional
groups in resin surface. Traditionally, in chloromethylated
polystyrene-divinylbenzene polymer, when undergoing quaternization,
each chloromethyl within the polymer can produce only one
quaternary ammonium group. The chloromethyl content within
chloromethylated polystyrene-divinylbenzene polymer is fixed
(16-20% by mass) and resistant to enhancement. This results in the
number of quaternary ammonium salt group in the resin surface being
impervious to enhancement since it is limited by the number of
chloromethyl. Therefore, it remains a difficult challenge to
increase the number of the quaternary ammonium salt groups deriving
from the chloromethyl on the chloromethylated
polystyrene-divinylbenzene polymer.
DESCRIPTIONS
1. The Technical Challenge Intended to be Solved by the
Invention
[0004] (1) The existing ion exchange resin for removing nitrate
ions in water are predominantly strong base type anion exchange
resin, wherein the adsorbing capacity for nitrate ion depends on
the number of amino/amine groups on the ion exchange resin, since
the nitrate ions preferably undergo ion exchange with the strong
base type ion exchange groups before the weak base type ion
exchange groups. However, under the traditional synthesis process
of the strong base type anion exchange resin with
polystyrene-divinylbenzene as matrix, each chloromethyl can only be
grafted with one quaternary ammonium salt group during the
quaternization reaction of the chloromethylated
polystyrene-divinylbenzene polymer. This limits the number of
strong base type ion exchange groups on the resin surface, as a
result the adsorption capacity for nitrate ion is resistant to
significant improvement. Therefore, increasing the number of ion
exchange groups within an ion exchange resin is the first technical
challenge to be solved.
[0005] (2) Natural waterbodies or wastewater generally contains the
phytic acid type of natural organic matter (tannic acid, gallic
acid). These natural organic matter not only react with the
amino/amine groups of the anion exchange resin and compete with
nitrate ions for adsorption resulting in decreased adsorption
capacity for nitrate ions, but also generate disinfection
byproducts during water disinfection treatment process that is
harmful to human health. At present, the absorbing material that
can effectively adsorb and remove phytic acid organic matter in
water is predominantly the weak base type ion exchange resin
containing primary amine, secondary amine and tertiary amine group,
because the phytic acid preferably reacts with the weak base type
ion exchange group over the strong base ion exchange group.
Therefore, the simultaneous introduction of the weak base type ion
exchange groups into the strong base type ion exchange resin, the
preferential adsorption of phytic acid type of matter in water, to
ensure that a sufficient number of the strong base type ion
exchange groups to be present within the resin to react with
nitrate ions, are another technical challenge that needs to be
solved.
[0006] (3) The conventional anion exchange resin synthesis method
usually employs chloromethylated polystyrene-divinylbenzene to
undergo amination reaction with dimethylamine, or to undergo
quaternization reaction with trimethylamine. For the anion exchange
resin produced by this method, a further increase the amino or
quaternary ammonium salt groups within the resin becomes difficult
to achieve. This is also a technical challenge that needs to be
solved.
[0007] In view of the above three challenges, the present invention
provides a high exchange-capacity anion exchange resin containing
dual functional-groups of a strong base type ion exchange group and
a weak base ion exchange group, and a method of synthesis thereof.
The synthesis method is simple and easy to operate, and can
introduce weak base type and strong base type ion exchange group
simultaneously onto the chloromethyl group of chloromethylated
polystyrene-divinylbenzene polymer, which significantly improves
the ion exchange capacity of the resin. Not only the resin's
adsorption capacity for nitrate ions is significantly improved, but
also the weak base type ion exchange group can contribute to the
removal of the phytic acid type organic matter in water, reducing
the competitive effect of the phytic acid on the removal of nitrate
ions during adsorption processes.
2. Technical Solutions
[0008] A high exchange-capacity anion exchange resin with dual
functional-groups uses chloromethylated polystyrene-divinylbenzene
polymer as matrix. The high exchange-capacity anion exchange resin
with dual functional-groups has a total exchange capacity of
6.3.about.7.9 mmol/g, wherein the strong base exchange capacity is
3.8.about.4.7 mmol/g, the weak base exchange capacity is
2.5.about.3.2 mmol/g, and the average particle diameter of the
resin is 550.about.650 .mu.m. Primary amine, serving as weak base
anion exchange group, is first grafted onto the chloromethylated
polystyrene-divinylbenzene polymer matrix;
3-chloro-2-hydroxypropyltrimethylammonium chloride, serving as
strong base anion exchange group, is subsequently grafted onto the
primary amine, yielding the high exchange-capacity, dual
functional-groups anion exchange resin having both weak base and
strong base anion exchange groups, and having the general formula
I:
##STR00001##
wherein, m is the degree of polymerization and within the range of
3000 to 5000, as determined by gel permeation chromatography. The
determination can be performed in accordance with reference "Ersi
Yang, Determination of Molecular Weight and Distribution of High
Impact Polystyrene by Gel Permeation Chromatography. Jilin Chemical
Science and Technology, 1997, 2: 26-28", the content of which is
incorporated in its entirety.
[0009] A high exchange-capacity anion exchange resin with dual
functional-groups is synthesized by using chloromethylated
polystyrene-divinylbenzene polymer as matrix, introducing weak base
ion exchange group (primary amine) to the matrix, further
introducing strong base ion exchange group (quaternary ammonium
salt group), and yielding a novel dual functional-groups anion
exchange resin. The synthesis process is further illustrated
infra.
Step 1:
##STR00002##
[0010] Step 2:
##STR00003##
[0011] In one embodiment of the invention, the detailed synthesis
steps are:
[0012] (1) Primary Amination Reaction
[0013] Into a mixed solution of anhydrous ethanol and chloroform,
chloromethylated polystyrene-divinylbenzene polymer was dissolved
to swell, hexamethylenetetramine was added, the reaction mixture
was stirred at 35-45.degree. C. for 6-7 hours; the polymer was
filtered, washed with ethanol, and placed into a mixed acid
solution of concentrated hydrochloric acid-anhydrous ethanol, with
the chloromethylated polystyrene-divinylbenzene polymer (g):mixed
acid solution (ml)=1:4-5, the reaction was kept at 35-45.degree. C.
for 2-3 hours, the polymer was filtered again, washed with water,
NaOH solution was added to keep pH>14 to transition for 2-3
hours, washed with water, and filtered to afford the
poly(divinylbenzene-vinylbenzyl amine) polymer;
[0014] (2) Quaternization Reaction
[0015] To a mixed solution formulation of
3-chloro-2-hydroxypropyltrimethylammonium chloride aqueous solution
and NaOH, the poly(divinylbenzene-vinylbenzyl amine) polymers from
step (1) is added, with the poly(divinylbenzene-vinylbenzyl amine)
polymers (g):the mixed solution formulation (ml)=1-2:50, the
reaction mixture was stirred at 70-80.degree. C. for 2-3 hours, the
product was washed with 10-30% HCl solution and deionized water,
dried in vacuum at 40-60.degree. C., to afford high
exchange-capacity anion exchange resin with dual
functional-groups.
[0016] In one embodiment, in the step (1) above, into a mixed
solution of anhydrous ethanol and chloroform, chloromethylated
polystyrene-divinylbenzene polymer was dissolved to swell at
20-25.degree. C. for for 3-4 hours; with the ratio of
chloromethylated polystyrene-divinylbenzene polymer (g):anhydrous
ethanol (ml):chloroform (ml):hexamethylenetetramine (g) being equal
to 5:15.about.20:2.about.4:4.about.5.
[0017] In another embodiment, in the step (1) above, the mixed acid
solution of concentrated hydrochloric acid-anhydrous ethanol is a
mixed acid solution formulation of 37.5% (mass %) concentrated HCl
mixed with anhydrous ethanol, with concentrated HCl (ml):anhydrous
ethanol (ml) in the range of 1:2-3.
[0018] In still another embodiment, in the step (1) above, NaOH
solution was added to keep pH>14 to transition for 2-3 hours,
wherein the NaOH solution is 1% (mass %).
[0019] In yet another embodiment, the
3-chloro-2-hydroxypropyltrimethylammonium chloride aqueous solution
in the step (2) is 60% (mass %), the NaOH solution is 40% (mass %),
and the ratio between the 3-chloro-2-hydroxypropyltrimethylammonium
chloride aqueous solution and the NaOH solution is 8-10:1 in
volume; the vacuum drying step is performed under the pressure of
-0.09.about.-0.08 MPa for 12-24 hours.
3. Beneficial Effects
[0020] The present invention provides synthesis method for a high
exchange-capacity anion exchange resin with dual functional-groups,
in which the total exchange capacity reaches 6.3.about.7.9 mmol/g,
wherein the strong base exchange capacity is 3.8.about.4.7 mmol/g,
the weak base exchange capacity is 2.5.about.3.2 mmol/g. The
absorption material comprises both a weak base type anion exchange
group and a strong base anion exchange group, thus enabling the
removal of phytic acid type of organic matter via the weak base
type anion exchange group while simultaneous removing of nitrate
ions, and achieving dual functionalization in the real-life water
treatment process. The invention has a broad application potential
in the fields of drinking water treatment, groundwater remediation,
and advanced urban sewage treatment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a molecular formula of the high exchange-capacity
anion exchange resin with dual functional-groups prepared by the
examples 1-12 of the present invention.
[0022] FIG. 2 is a FT-IR spectrum of the high exchange-capacity
anion exchange resin with dual functional-groups (i.e., the new
resin in the Figure) prepared in Example 1. The x-axis is the wave
number and the y-axis the transmittance. The chart represents
transmittance of various infrared light for samples.
[0023] FIG. 3 is a solid nuclear magnetic resonance spectrum of the
high exchange-capacity anion exchange resin with dual
functional-groups prepared in Example 1. The x-axis is chemical
shift.
[0024] FIG. 4 is a scanning electron micrograph of the high
exchange-capacity anion exchange resin with dual functional-groups
prepared in Example 1.
EXAMPLES
[0025] The invention is now further described by reference to the
following examples which are intended to illustrate, not to limit
the scope of the invention.
Example 1
[0026] A method for synthesizing a high exchange-capacity anion
exchange resin with dual functional-groups, comprising the steps
of:
[0027] 1) Primary Amination Reaction
[0028] 5 g of chloromethylated polystyrene-divinylbenzene polymer
(degree of polymerization m=3000) was placed into stirred solution
of 15 ml anhydrous ethanol and 2 ml chloroform, swell at 20.degree.
C. for 3 hours, 4 g of hexamethylenetetramine was added, the
reaction mixture was stirred at 35.degree. C. for 6 hours. The
polymer was filtered and washed with ethanol. Concentrated
hydrochloric acid (37.5% mass percentage) and anhydrous ethanol was
mixed into an acid hydrolysis solution, with the concentrated
hydrochloric acid volume (ml):anhydrous ethanol volume (ml)=1:2.
The polymer was added to the acid hydrolysis solution, with the
chloromethylated polystyrene-divinylbenzene polymer (g):acid
hydrolysis solution (ml)=1:4. React at 35.degree. C. for 2 hours.
The polymer was filtered, washed with water, allowed to transition
for 2-3 hours with 1% NaOH solution added to control pH>14,
washed with water, and filtered to afford
poly(divinylbenzene-vinylbenzyl amine) polymer;
##STR00004##
[0029] 2) Quaternization Reaction
[0030] 60% 3-chloro-2-hydroxypropyltrimethylammonium chloride
aqueous solution and 40% NaOH solution were mixed, the ratio of the
two solutions being 8:1 (volume:volume). The
poly(divinylbenzene-vinylbenzyl amine) polymer from the step 1) is
added into the mixed solution, at the ratio of polymer (g):mixed
solution (ml)=1:50, stired at 70.degree. C. for two hours. The
reaction product was washed with 10% hydrochloric acid and
deionized water, dried at 40.degree. C. in vacuum for 12 hours
(pressure -0.09 Mpa) to afford the high exchange-capacity anion
exchange resin with dual functional-groups.
##STR00005##
[0031] In test, the maximum adsorption capacity for nitrate ion was
198.5 mg/g, the maximum adsorption capacity for tannic acid was
493.7 mg/g, and the maximum adsorption capacity for gallic acid was
407.6 mg/g. The total exchange capacity of the resin was 7.9
mmol/g, with a strong base exchange capacity of 4.7 mmol/g, a weak
base exchange capacity of 3.2 mmol/g, and an average resin particle
size of 550 .mu.m.
[0032] FIG. 1 is a structure diagram of the high exchange-capacity
anion exchange resin with dual functional-groups prepared from a
method described in Example 1.
[0033] FIG. 2 is the FT-IR spectrum of the high exchange-capacity
anion exchange resin with dual functional-groups prepared from
method described in Examples of present invention. In the spectrum
of poly(divinylbenzene-vinylbenzyl amine) polymer, the absorption
peak of N--H bending vibration in --NH.sub.2 is shown at 1564
cm.sup.-1, indicating that the primary amine group has been
successfully grafted in the reaction step 1; in the infrared
spectrum of the new resin (the high exchange-capacity anion
exchange resin with dual functional-groups prepared in the examples
of the present invention), the absorption peak of the -NH.sub.2
almost disappeared, in its place a strong absorption peak at 1476
cm.sup.-1 appeared, precisely corresponding to the bending
vibration of N--CH.sub.3 in the trimethylammonium chloride group.
Meanwhile the emerging absorption peak at 1100 cm.sup.-1
corresponds to the stretching vibration of C--O. FIG. 3 is a solid
nuclear magnetic resonance spectrum of high exchange-capacity anion
exchange resin with dual functional-groups prepared from the
examples of the current invention. Combining infrared spectroscopy
analysis from FIG. 2 and NMR analysis from FIG. 3 can confirm the
structure of the high exchange-capacity anion exchange resin with
dual functional-groups as shown in FIG. 1. FIG. 4 is a scanning
electron micrograph of the high exchange-capacity anion exchange
resin with dual functional-groups prepared from the examples of the
present invention.
Example 2
[0034] A method for synthesizing a high exchange-capacity anion
exchange resin with dual functional-groups, comprising the steps
of:
[0035] 1) Primary Amination Reaction
[0036] 5 g of chloromethylated polystyrene-divinylbenzene polymer
(degree of polymerization m=3530) was placed into stirred solution
of 15 ml anhydrous ethanol and 2 ml chloroform, swell at 20.degree.
C. for 3 hours, 4 g of hexamethylenetetramine was added, the
reaction mixture was stirred at 35.degree. C. for 6 hours. The
polymer was filtered and washed with ethanol. Concentrated
hydrochloric acid (37.5% mass percentage) and anhydrous ethanol was
mixed into an acid hydrolysis solution, with the concentrated
hydrochloric acid volume (ml): anhydrous ethanol volume (ml)=1:2.
The polymer was added to the acid hydrolysis solution, with the
chloromethylated polystyrene-divinylbenzene polymer (g):acid
hydrolysis solution (ml)=1:4. React at 35.degree. C. for 2 hours.
The polymer was filtered, washed with water, allowed to transition
for 2-3 hours with 1% NaOH solution added to control pH>14,
washed with water, and filtered to afford
poly(divinylbenzene-vinylbenzyl amine) polymer;
[0037] 2) Quaternization Reaction
[0038] 60% 3-chloro-2-hydroxypropyltrimethylammonium chloride
aqueous solution and 40% NaOH solution were mixed, the ratio of the
two solutions being 9:1 (volume:volume). The
poly(divinylbenzene-vinylbenzyl amine) polymer from the step 1) is
added into the mixed solution, at the ratio of polymer (g):mixed
solution (ml)=1.5:50, stired at 75.degree. C. for 2.5 hours. The
reaction product was washed with 20% hydrochloric acid and
deionized water, dried at 50.degree. C. in vacuum for 18 hours
(pressure -0.085 Mpa) to afford the high exchange-capacity anion
exchange resin with dual functional-groups.
[0039] The synthezied resin has characteristics significantly
similar to that from Example 1. The maximum adsorption capacity for
nitrate was 173.3 mg/g, the maximum adsorption capacity for tannic
acid was 466.5 mg/g, and the maximum adsorption capacity for gallic
acid was 379.2 mg/g. The total exchange capacity of the resin was
6.6 mmol/g, with a strong base exchange capacity of 3.9 mmol/g, a
weak base exchange capacity of 2.7 mmol/g, and an average resin
particle size of 600 .mu.m.
Example 3
[0040] A method for synthesizing a high exchange-capacity anion
exchange resin with dual functional-groups, comprising the steps
of:
[0041] 1) Primary Amination Reaction
[0042] 5 g of chloromethylated polystyrene-divinylbenzene polymer
(degree of polymerization m=3870) was placed into stirred solution
of 15 ml anhydrous ethanol and 2 ml chloroform, swell at 20.degree.
C. for 3 hours, 4 g of hexamethylenetetramine was added, the
reaction mixture was stirred at 35.degree. C. for 6 hours. The
polymer was filtered and washed with ethanol. Concentrated
hydrochloric acid (37.5% mass percentage) and anhydrous ethanol was
mixed into an acid hydrolysis solution, with the concentrated
hydrochloric acid volume (ml):anhydrous ethanol volume (ml)=1:2.
The polymer was added to the acid hydrolysis solution, with the
chloromethylated polystyrene-divinylbenzene polymer (g):acid
hydrolysis solution (ml)=1:4. React at 35.degree. C. for 2 hours.
The polymer was filtered, washed with water, allowed to transition
for 2-3 hours with 1% NaOH solution added to control pH>14,
washed with water, and filtered to afford
poly(divinylbenzene-vinylbenzyl amine) polymer;
[0043] 2) Quaternization Reaction
[0044] 60% 3-chloro-2-hydroxypropyltrimethylammonium chloride
aqueous solution and 40% NaOH solution were mixed, the ratio of the
two solutions being 10:1 (volume:volume). The
poly(divinylbenzene-vinylbenzyl amine) polymer from the step 1) is
added into the mixed solution, at the ratio of polymer (g):mixed
solution (ml)=2:50, stired at 80.degree. C. for 3 hours. The
reaction product was washed with 30% hydrochloric acid and
deionized water, dried at 60.degree. C. in vacuum for 24 hours
(pressure -0.085 Mpa) to afford the high exchange-capacity anion
exchange resin with dual functional-groups.
[0045] The synthezied resin has characteristics significantly
similar to that from Example 1. The maximum adsorption capacity for
nitrate ion was 175.1 mg/g, the maximum adsorption capacity for
tannic acid was 468.7 mg/g, and the maximum adsorption capacity for
gallic acid was 381.4 mg/g. The total exchange capacity of the
resin was 6.6 mmol/g, with a strong base exchange capacity of 3.8
mmol/g, a weak base exchange capacity of 2.8 mmol/g, and an average
resin particle size of 580 .mu.m.
Example 4
[0046] A method for synthesizing a high exchange-capacity anion
exchange resin with dual functional-groups, comprising the steps
of:
[0047] 1) Primary Amination Reaction
[0048] 5 g of chloromethylated polystyrene-divinylbenzene polymer
(degree of polymerization m=3870) was placed into stirred solution
of 17 ml anhydrous ethanol and 3 ml chloroform, swell at 20.degree.
C. for 3.5 hours, 4.5 g of hexamethylenetetramine was added, the
reaction mixture was stirred at 40.degree. C. for 6.5 hours. The
polymer was filtered and washed with ethanol. Concentrated
hydrochloric acid (37.5% mass percentage) and anhydrous ethanol was
mixed into an acid hydrolysis solution, with the concentrated
hydrochloric acid volume (ml):anhydrous ethanol volume (ml)=1:2.5.
The polymer was added to the acid hydrolysis solution, with the
chloromethylated polystyrene-divinylbenzene polymer (g):acid
hydrolysis solution (ml)=1:4.5. React at 40.degree. C. for 2.5
hours. The polymer was filtered, washed with water, allowed to
transition for 2.5 hours with 1% NaOH solution added to control
pH>14, washed with water, and filtered to afford
poly(divinylbenzene-vinylbenzyl amine) polymer;
[0049] 2) Quaternization Reaction
[0050] 60% 3-chloro-2-hydroxypropyltrimethylammonium chloride
aqueous solution and 40% NaOH solution were mixed, the ratio of the
two solutions being 8:1 (volume:volume). The
poly(divinylbenzene-vinylbenzyl amine) polymer from the step 1) is
added into the mixed solution, at the ratio of polymer (g):mixed
solution (ml)=1:50, stired at 70.degree. C. for 2 hours. The
reaction product was washed with 10% hydrochloric acid and
deionized water, dried at 40.degree. C. in vacuum for 12 hours
(pressure -0.09 Mpa) to afford the high exchange-capacity anion
exchange resin with dual functional-groups.
[0051] The synthezied resin has characteristics significantly
similar to that from Example 1. The maximum adsorption capacity for
nitrate ion was 185.5 mg/g, the maximum adsorption capacity for
tannic acid was 481.5 mg/g, and the maximum adsorption capacity for
gallic acid was 400.4 mg/g. The total exchange capacity of the
resin was 7.1 mmol/g, with a strong base exchange capacity of 4.2
mmol/g, a weak base exchange capacity of 2.9 mmol/g, and an average
resin particle size of 590 .mu.m.
Example 5
[0052] A method for synthesizing a high exchange-capacity anion
exchange resin with dual functional-groups, comprising the steps
of:
[0053] 1) Primary Amination Reaction
[0054] 5 g of chloromethylated polystyrene-divinylbenzene polymer
(degree of polymerization m=4880) was placed into stirred solution
of 17 ml anhydrous ethanol and 3 ml chloroform, swell at 20.degree.
C. for 3.5 hours, 4.5 g of hexamethylenetetramine was added, the
reaction mixture was stirred at 40.degree. C. for 6.5 hours. The
polymer was filtered and washed with ethanol. Concentrated
hydrochloric acid (37.5% mass percentage) and anhydrous ethanol was
mixed into an acid hydrolysis solution, with the concentrated
hydrochloric acid volume (ml):anhydrous ethanol volume (ml)=1:2.5.
The polymer was added to the acid hydrolysis solution, with the
chloromethylated polystyrene-divinylbenzene polymer (g):acid
hydrolysis solution (ml)=1:4.5. React at 40.degree. C. for 2.5
hours. The polymer was filtered, washed with water, allowed to
transition for 2.5 hours with 1% NaOH solution added to control
pH>14, washed with water, and filtered to afford
poly(divinylbenzene-vinylbenzyl amine) polymer;
[0055] 2) Quaternization Reaction
[0056] 60% 3-chloro-2-hydroxypropyltrimethylammonium chloride
aqueous solution and 40% NaOH solution were mixed, the ratio of the
two solutions being 9:1 (volume:volume). The
poly(divinylbenzene-vinylbenzyl amine) polymer from the step 1) is
added into the mixed solution, at the ratio of polymer (g):mixed
solution (ml)=1.5:50, stired at 75.degree. C. for 2.5 hours. The
reaction product was washed with 20% hydrochloric acid and
deionized water, dried at 50.degree. C. in vacuum for 18 hours
(pressure -0.085 Mpa) to afford the high exchange-capacity anion
exchange resin with dual functional-groups.
[0057] The synthezied resin has characteristics significantly
similar to that from Example 1. The maximum adsorption capacity for
nitrate ion was 187.2 mg/g, the maximum adsorption capacity for
tannic acid was 487.1 mg/g, and the maximum adsorption capacity for
gallic acid was 406.7 mg/g. The total exchange capacity of the
resin was 7.0 mmol/g, with a strong base exchange capacity of 4.2
mmol/g, a weak base exchange capacity of 2.8 mmol/g, and an average
resin particle size of 600 .mu.m.
Example 6
[0058] A method for synthesizing a high exchange-capacity anion
exchange resin with dual functional-groups, comprising the steps
of:
[0059] 1) Primary Amination Reaction
[0060] 5 g of chloromethylated polystyrene-divinylbenzene polymer
(degree of polymerization m=5000) was placed into stirred solution
of 17 ml anhydrous ethanol and 3 ml chloroform, swell at 22.degree.
C. for 3.5 hours, 4.5 g of hexamethylenetetramine was added, the
reaction mixture was stirred at 40.degree. C. for 6.5 hours. The
polymer was filtered and washed with ethanol. Concentrated
hydrochloric acid (37.5% mass percentage) and anhydrous ethanol was
mixed into an acid hydrolysis solution, with the concentrated
hydrochloric acid volume (ml):anhydrous ethanol volume (ml)=1:2.5.
The polymer was added to the acid hydrolysis solution, with the
chloromethylated polystyrene-divinylbenzene polymer (g):acid
hydrolysis solution (ml)=1:4.5. React at 40.degree. C. for 2.5
hours. The polymer was filtered, washed with water, allowed to
transition for 2.5 hours with 1% NaOH solution added to control
pH>14, washed with water, and filtered to afford
poly(divinylbenzene-vinylbenzyl amine) polymer;
[0061] 2) Quaternization Reaction
[0062] 60% 3-chloro-2-hydroxypropyltrimethylammonium chloride
aqueous solution and 40% NaOH solution were mixed, the ratio of the
two solutions being 10:1 (volume:volume). The
poly(divinylbenzene-vinylbenzyl amine) polymer from the step 1) is
added into the mixed solution, at the ratio of polymer (g):mixed
solution (ml)=2:50, stired at 80.degree. C. for 3 hours. The
reaction product was washed with 30% hydrochloric acid and
deionized water, dried at 60.degree. C. in vacuum for 24 hours
(pressure -0.08 Mpa) to afford the high exchange-capacity anion
exchange resin with dual functional-groups.
[0063] The synthezied resin has characteristics significantly
similar to that from Example 1. The maximum adsorption capacity for
nitrate ion was 184.5 mg/g, the maximum adsorption capacity for
tannic acid was 488.3 mg/g, and the maximum adsorption capacity for
gallic acid was 395.6 mg/g. The total exchange capacity of the
resin was 7.1 mmol/g, with a strong base exchange capacity of 4.1
mmol/g, a weak base exchange capacity of 3.0 mmol/g, and an average
resin particle size of 630 .mu.m.
Example 7
[0064] A method for synthesizing a high exchange-capacity anion
exchange resin with dual functional-groups, comprising the steps
of:
[0065] 1) Primary Amination Reaction
[0066] 5 g of chloromethylated polystyrene-divinylbenzene polymer
(degree of polymerization m=3300) was placed into stirred solution
of 20 ml anhydrous ethanol and 4 ml chloroform, swell at 25.degree.
C. for 4 hours, 5 g of hexamethylenetetramine was added, the
reaction mixture was stirred at 45.degree. C. for 7 hours. The
polymer was filtered and washed with ethanol. Concentrated
hydrochloric acid (37.5% mass percentage) and anhydrous ethanol was
mixed into an acid hydrolysis solution, with the concentrated
hydrochloric acid volume (ml):anhydrous ethanol volume (ml)=1:3.
The polymer was added to the acid hydrolysis solution, with the
chloromethylated polystyrene-divinylbenzene polymer (g):acid
hydrolysis solution (ml)=1:5. React at 45.degree. C. for 3 hours.
The polymer was filtered, washed with water, allowed to transition
for 3 hours with 1% NaOH solution added to control pH>14, washed
with water, and filtered to afford poly(divinylbenzene-vinylbenzyl
amine) polymer;
[0067] 2) Quaternization Reaction
[0068] 60% 3-chloro-2-hydroxypropyltrimethylammonium chloride
aqueous solution and 40% NaOH solution were mixed, the ratio of the
two solutions being 8:1 (volume:volume). The
poly(divinylbenzene-vinylbenzyl amine) polymer from the step 1) is
added into the mixed solution, at the ratio of polymer (g):mixed
solution (ml)=1:50, stired at 70.degree. C. for 2 hours. The
reaction product was washed with 10% hydrochloric acid and
deionized water, dried at 40.degree. C. in vacuum for 12 hours
(pressure -0.09 Mpa) to afford the high exchange-capacity anion
exchange resin with dual functional-groups.
[0069] The synthezied resin has characteristics significantly
similar to that from Example 1. The maximum adsorption capacity for
nitrate ion was 185.5 mg/g, the maximum adsorption capacity for
tannic acid was 480.1 mg/g, and the maximum adsorption capacity for
gallic acid was 387.7 mg/g. The total exchange capacity of the
resin was 7.3 mmol/g, with a strong base exchange capacity of 4.2
mmol/g, a weak base exchange capacity of 3.1 mmol/g, and an average
resin particle size of 590 .mu.m.
Example 8
[0070] A method for synthesizing a high exchange-capacity anion
exchange resin with dual functional-groups, comprising the steps
of:
[0071] 1) Primary Amination Reaction
[0072] 5 g of chloromethylated polystyrene-divinylbenzene polymer
(degree of polymerization m=4150) was placed into stirred solution
of 20 ml anhydrous ethanol and 4 ml chloroform, swell at 25.degree.
C. for 4 hours, 5 g of hexamethylenetetramine was added, the
reaction mixture was stirred at 45.degree. C. for 7 hours. The
polymer was filtered and washed with ethanol. Concentrated
hydrochloric acid (37.5% mass percentage) and anhydrous ethanol was
mixed into an acid hydrolysis solution, with the concentrated
hydrochloric acid volume (ml):anhydrous ethanol volume (ml)=1:3.
The polymer was added to the acid hydrolysis solution, with the
chloromethylated polystyrene-divinylbenzene polymer (g):acid
hydrolysis solution (ml)=1:5. React at 45.degree. C. for 3 hours.
The polymer was filtered, washed with water, allowed to transition
for 3 hours with 1% NaOH solution added to control pH>14, washed
with water, and filtered to afford poly(divinylbenzene-vinylbenzyl
amine) polymer;
[0073] 2) Quaternization Reaction
[0074] 60% 3-chloro-2-hydroxypropyltrimethylammonium chloride
aqueous solution and 40% NaOH solution were mixed, the ratio of the
two solutions being 9:1 (volume:volume). The
poly(divinylbenzene-vinylbenzyl amine) polymer from the step 1) is
added into the mixed solution, at the ratio of polymer (g):mixed
solution (ml)=1.5:50, stired at 75.degree. C. for 2.5 hours. The
reaction product was washed with 20% hydrochloric acid and
deionized water, dried at 50.degree. C. in vacuum for 18 hours
(pressure -0.085 Mpa) to afford the high exchange-capacity anion
exchange resin with dual functional-groups.
[0075] The synthezied resin has characteristics significantly
similar to that from Example 1. The maximum adsorption capacity for
nitrate ion was 187.2 mg/g, the maximum adsorption capacity for
tannic acid was 478.2 mg/g, and the maximum adsorption capacity for
gallic acid was 384.6 mg/g. The total exchange capacity of the
resin was 7.3 mmol/g, with a strong base exchange capacity of 4.3
mmol/g, a weak base exchange capacity of 3.0 mmol/g, and an average
resin particle size of 620 .mu.m.
Example 9
[0076] A method for synthesizing a high exchange-capacity anion
exchange resin with dual functional-groups, comprising the steps
of:
[0077] 1) Primary Amination Reaction
[0078] 5 g of chloromethylated polystyrene-divinylbenzene polymer
(degree of polymerization m=3740) was placed into stirred solution
of 20 ml anhydrous ethanol and 4 ml chloroform, swell at 25.degree.
C. for 4 hours, 5 g of hexamethylenetetramine was added, the
reaction mixture was stirred at 45.degree. C. for 7 hours. The
polymer was filtered and washed with ethanol. Concentrated
hydrochloric acid (37.5% mass percentage) and anhydrous ethanol was
mixed into an acid hydrolysis solution, with the concentrated
hydrochloric acid volume (ml):anhydrous ethanol volume (ml)=1:3.
The polymer was added to the acid hydrolysis solution, with the
chloromethylated polystyrene-divinylbenzene polymer (g):acid
hydrolysis solution (ml)=1:5. React at 45.degree. C. for 3 hours.
The polymer was filtered, washed with water, allowed to transition
for 3 hours with 1% NaOH solution added to control pH>14, washed
with water, and filtered to afford poly(divinylbenzene-vinylbenzyl
amine) polymer;
[0079] 2) Quaternization Reaction
[0080] 60% 3-chloro-2-hydroxypropyltrimethylammonium chloride
aqueous solution and 40% NaOH solution were mixed, the ratio of the
two solutions being 10:1 (volume:volume). The
poly(divinylbenzene-vinylbenzyl amine) polymer from the step 1) is
added into the mixed solution, at the ratio of polymer (g):mixed
solution (ml)=2:50, stired at 75.degree. C. for 3 hours. The
reaction product was washed with 30% hydrochloric acid and
deionized water, dried at 60.degree. C. in vacuum for 24 hours
(pressure -0.08 Mpa) to afford the high exchange-capacity anion
exchange resin with dual functional-groups.
[0081] The synthezied resin has characteristics significantly
similar to that from Example 1. The maximum adsorption capacity for
nitrate ion was 184.5 mg/g, the maximum adsorption capacity for
tannic acid was 466.9 mg/g, and the maximum adsorption capacity for
gallic acid was 376.7 mg/g. The total exchange capacity of the
resin was 7.0 mmol/g, with a strong base exchange capacity of 3.9
mmol/g, a weak base exchange capacity of 3.1 mmol/g, and an average
resin particle size of 610 .mu.m.
Example 10
[0082] A method for synthesizing a high exchange-capacity anion
exchange resin with dual functional-groups, comprising the steps
of:
[0083] 1) Primary Amination Reaction
[0084] 5 g of chloromethylated polystyrene-divinylbenzene polymer
(degree of polymerization m=4560) was placed into stirred solution
of 15 ml anhydrous ethanol and 2 ml chloroform, swell at 20.degree.
C. for 4 hours, 4 g of hexamethylenetetramine was added, the
reaction mixture was stirred at 35.degree. C. for 6 hours. The
polymer was filtered and washed with ethanol. Concentrated
hydrochloric acid (37.5% mass percentage) and anhydrous ethanol was
mixed into an acid hydrolysis solution, with the concentrated
hydrochloric acid volume (ml):anhydrous ethanol volume (ml)=1:2.
The polymer was added to the acid hydrolysis solution, with the
chloromethylated polystyrene-divinylbenzene polymer (g):acid
hydrolysis solution (ml)=1:5. React at 45.degree. C. for 2 hours.
The polymer was filtered, washed with water, allowed to transition
for 3 hours with 1% NaOH solution added to control pH>14, washed
with water, and filtered to afford poly(divinylbenzene-vinylbenzyl
amine) polymer;
[0085] 2) Quaternization Reaction
[0086] 60% 3-chloro-2-hydroxypropyltrimethylammonium chloride
aqueous solution and 40% NaOH solution were mixed, the ratio of the
two solutions being 8:1 (volume:volume). The
poly(divinylbenzene-vinylbenzyl amine) polymer from the step 1) is
added into the mixed solution, at the ratio of polymer (g):mixed
solution (ml)=1.5:50, stired at 75.degree. C. for 2.5 hours. The
reaction product was washed with 20% hydrochloric acid and
deionized water, dried at 50.degree. C. in vacuum for 18 hours
(pressure -0.085 Mpa) to afford the high exchange-capacity anion
exchange resin with dual functional-groups.
[0087] The synthezied resin has characteristics significantly
similar to that from Example 1. The maximum adsorption capacity for
nitrate ion was 171.7 mg/g, the maximum adsorption capacity for
tannic acid was 459.6 mg/g, and the maximum adsorption capacity for
gallic acid was 375.4 mg/g. The total exchange capacity of the
resin was 6.3 mmol/g, with a strong base exchange capacity of 3.8
mmol/g, a weak base exchange capacity of 2.5 mmol/g, and an average
resin particle size of 650 .mu.m.
Example 11
[0088] A method for synthesizing a high exchange-capacity anion
exchange resin with dual functional-groups, comprising the steps
of:
[0089] 1) Primary Amination Reaction
[0090] 5 g of chloromethylated polystyrene-divinylbenzene polymer
(degree of polymerization m=3890) was placed into stirred solution
of 15 ml anhydrous ethanol and 2 ml chloroform, swell at 20.degree.
C. for 4 hours, 4 g of hexamethylenetetramine was added, the
reaction mixture was stirred at 35.degree. C. for 6 hours. The
polymer was filtered and washed with ethanol. Concentrated
hydrochloric acid (37.5% mass percentage) and anhydrous ethanol was
mixed into an acid hydrolysis solution, with the concentrated
hydrochloric acid volume (ml):anhydrous ethanol volume (ml)=1:3.
The polymer was added to the acid hydrolysis solution, with the
chloromethylated polystyrene-divinylbenzene polymer (g):acid
hydrolysis solution (ml)=1:4. React at 45.degree. C. for 3 hours.
The polymer was filtered, washed with water, allowed to transition
for 2 hours with 1% NaOH solution added to control pH>14, washed
with water, and filtered to afford poly(divinylbenzene-vinylbenzyl
amine) polymer;
[0091] 2) Quaternization Reaction
[0092] 60% 3-chloro-2-hydroxypropyltrimethylammonium chloride
aqueous solution and 40% NaOH solution were mixed, the ratio of the
two solutions being 9:1 (volume:volume). The
poly(divinylbenzene-vinylbenzyl amine) polymer from the step 1) is
added into the mixed solution, at the ratio of polymer (g):mixed
solution (ml)=2:50, stired at 80.degree. C. for 3 hours. The
reaction product was washed with 30% hydrochloric acid and
deionized water, dried at 60.degree. C. in vacuum for 24 hours
(pressure -0.08 Mpa) to afford the high exchange-capacity anion
exchange resin with dual functional-groups.
[0093] The synthezied resin has characteristics significantly
similar to that from Example 1. The maximum adsorption capacity for
nitrate ion was 179.1 mg/g, the maximum adsorption capacity for
tannic acid was 466.5 mg/g, and the maximum adsorption capacity for
gallic acid was 383.7 mg/g. The total exchange capacity of the
resin was 6.5 mmol/g, with a strong base exchange capacity of 3.8
mmol/g, a weak base exchange capacity of 2.7 mmol/g, and an average
resin particle size of 620 .mu.m.
Example 12
[0094] A method for synthesizing a high exchange-capacity anion
exchange resin with dual functional-groups, comprising the steps
of:
[0095] 1) Primary Amination Reaction
[0096] 5 g of chloromethylated polystyrene-divinylbenzene polymer
(degree of polymerization m=3470) was placed into stirred solution
of 17 ml anhydrous ethanol and 3 ml chloroform, swell at 20.degree.
C. for 4 hours, 4.5 g of hexamethylenetetramine was added, the
reaction mixture was stirred at 40.degree. C. for 6.5 hours. The
polymer was filtered and washed with ethanol. Concentrated
hydrochloric acid (37.5% mass percentage) and anhydrous ethanol was
mixed into an acid hydrolysis solution, with the concentrated
hydrochloric acid volume (ml):anhydrous ethanol volume (ml)=1:2.5.
The polymer was added to the acid hydrolysis solution, with the
chloromethylated polystyrene-divinylbenzene polymer (g):acid
hydrolysis solution (ml)=1:5. React at 45.degree. C. for 3 hours.
The polymer was filtered, washed with water, allowed to transition
for 2.5 hours with 1% NaOH solution added to control pH>14,
washed with water, and filtered to afford
poly(divinylbenzene-vinylbenzyl amine) polymer;
[0097] 2) Quaternization Reaction
[0098] 60% 3-chloro-2-hydroxypropyltrimethylammonium chloride
aqueous solution and 40% NaOH solution were mixed, the ratio of the
two solutions being 10:1 (volume:volume). The
poly(divinylbenzene-vinylbenzyl amine) polymer from the step 1) is
added into the mixed solution, at the ratio of polymer (g):mixed
solution (ml)=1:50, stired at 70.degree. C. for 2 hours. The
reaction product was washed with 10% hydrochloric acid and
deionized water, dried at 40.degree. C. in vacuum for 12 hours
(pressure -0.09 Mpa) to afford the high exchange-capacity anion
exchange resin with dual functional-groups.
[0099] The synthezied resin has characteristics significantly
similar to that from Example 1. The maximum adsorption capacity for
nitrate ion was 189.5 mg/g, the maximum adsorption capacity for
tannic acid was 477.5 mg/g, and the maximum adsorption capacity for
gallic acid was 398.8 mg/g. The total exchange capacity of the
resin was 7.5 mmol/g, with a strong base exchange capacity of 4.3
mmol/g, a weak base exchange capacity of 3.2 mmol/g, and an average
resin particle size of 610 .mu.m.
* * * * *